Effect of Carbon Forms on Properties of Ag-C Composites Contact Materials

This paper presents the manufacturing method of silver based composite materials containing 3 % vol. carbon forms (nanotubes and graphene). The most significant challenge was to obtain good dispersion of carbon in the metallic matrix. The applying of suitable dispersants allows to get uniform distribution of carbon reinforcement. Triton X-100 and ultrasonic support were used in the powder mixing process. Ag-nanotubes and Ag-graphene contact tips were made using Spark Plasma Sintering process (SPS). The results of research into both physical and electrical properties of these composites are presented. It has been demonstrated that the form of introduced carbon exerts influence on the electrical characteristics of contacts, and particularly on arc erosion. Performed electrical test indicated that Ag-nanotubes contacts showed higher resistance to arc erosion than Ag‑graphene contacts. It can be explained by the better dispersion to individual carbon nanotubes their lower than for graphene edge defects density and due to this higher thermal and electrical conductivity.DOI: http://dx.doi.org/10.5755/j01.ms.24.1.17769